TROJ_REMDOBE.UJK

 Analysis by: Nikko Tamana

 ALIASES:

W32/Agent.YZUB!tr (Fortinet), Trojan.Win32.Agent.yzub (Kaspersky), Trojan:MSIL/Remdobe (Microsoft)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet, Dropped by other malware

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It is injected into all running processes to remain memory resident.

However, as of this writing, the said sites are inaccessible. It deletes the initially executed copy of itself.

  TECHNICAL DETAILS

File Size:

95,232 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

10 Jun 2013

Payload:

Connects to URLs/IPs, Downloads files

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This Trojan drops the following copies of itself into the affected system:

  • %Application Data%\AlienWare\vAlien.exe

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

It creates the following folders:

  • %Application Data%\AlienWare

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

It is injected into all running processes to remain memory resident.

It adds the following mutexes to ensure that only one of its copies runs at any one time:

  • {random characters}

Other Details

This Trojan attempts to access the following websites to download files, which are possibly malicious:

  • http://dl.{BLOCKED}x.com/FileToDownload.exe
  • http://{BLOCKED}nzo.pw/1370687939_0.80426800.exe
  • http://{BLOCKED}olumers.info/1370732239_0.51267400.exe

However, as of this writing, the said sites are inaccessible.

It deletes the initially executed copy of itself

  SOLUTION

Minimum Scan Engine:

9.300

FIRST VSAPI PATTERN FILE:

9.988.02

FIRST VSAPI PATTERN DATE:

18 Jun 2013

VSAPI OPR PATTERN File:

9.989.00

VSAPI OPR PATTERN Date:

19 Jun 2013

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Restart in Safe Mode

[ Learn More ]

Step 3

Search and delete this folder

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %Application Data%\AlienWare

Step 4

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_REMDOBE.UJK. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.


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